The proposed research is to continue fundamental studies on the physical-chemical functions and chemical reactivity of hydrophilic colloids (food stabilizers) in biological systems, for the purpose of obtaining information by which these additives may be judicially selected for use in food stabilization. The investigation will continue to deal with the significance of the chemical structure and configuration of selected polysaccharides, including carrageenan, carboxymethylcellulose, alginates, and locust bean gum for their interactions with proteins, lipids, lipoproteins, and salts in model systems. Improved methods will be used to delineate the fate of specific stabilizers in processed foods in order to determine if fragmentation, hydrolysis, or chemical modifications may occur and which may cause adverse nutritional effects. Particular emphasis will be given to the determination of molecular weights by sedimentation equilibrium approaches to screen the hydrocolloids for low molecular polysaccharides which have been demonstrated to be potentially dangerous to health. A search will be initiated for alternative stabilizing agents which may replace carrageenans for use in evaporated milk and manufactured infant formula. Studies will continue to examine possible unrecognized health problems related to the complexing of proteins with food stabilizers in the digestive tract. The complex formation between hydrocolloids and enzymes will be examined for reversibility and functional properties.